Device and method for fragmenting and removing concretions from body ducts and cavities

ABSTRACT

A medical device and method for breaking a concretion in a body into smaller pieces and removing the pieces from the body are described. The device comprises a dilator sheath, a lithotripsy probe, a tubular member, and a retrieval basket. The dilator sheath adapted to penetrate into a passage of the body to reach the location where the concretion is located. The lithotripsy probe is configured for shattering the concretion into smaller pieces. The tubular member is mounted within the dilator sheath adapted to permit the lithotripsy probe to be inserted into the tubular member. The retrieval basket is coupled to the tubular member, and configured for entrapping the concretion and the smaller pieces for their extraction from the body. The retrieval basket comprises a structure constituted by a plurality of filaments extending from a basket proximal end towards a basket distal end, and then returning to the proximal end after forming a plurality of filament loops in the basket distal portion, and a plurality of filament strands at the basket proximal portion.

FIELD OF THE INVENTION

This invention relates to a device and method for fragmenting abnormalconcretions and extracting their pieces from hollow bodies, and inparticular, to a medical instrument for fragmenting and removing solidcalculous formations from the ducts and cavities of a living body.

BACKGROUND OF THE INVENTION

Several techniques are employed in clinical practice for breakingabnormal concretions appearing in the biliary and/or urinary system of ahuman body into pieces for further removal of the pieces from the body.The term “concretion” as used herein refers to solid calculousformations of urates, oxalates and phosphates, e.g. gallstones, kidneystones, cystine stones and other calculi, lodged in the ducts andcavities of a living body. Although procedures have varied, most of themhave involved dilatating, anesthetizing and lubricating the urinary orbiliary tract, and then attempting to grasp the calculus for crushingit, and then dragging it out.

For example, extra- and intra-corporeal shock wave lithotripsy is widelyused which employs high-energy shock waves to fragment and disintegratecalculi. In extracorporeal shock-wave lithotripsy, an energy needed forstone fragmentation, in the form of shock waves, is transferred from anoutside source through body tissue to the calculi. In turn,intra-corporeal shock wave lithotripsy utilizes a probe advanced withthe aim of an endoscope and positioned in proximity to the calculus. Theshock waves, required for fragmentation, are transferred through theprobe to the calculus, and the treatment process can be visualizedduring fragmentation.

Ultrasonic lithotripsy technique is known that utilizes an ultrasoundprobe emitting high-frequency ultrasonic energy towards a concretion.For this technique, direct contact of the probe tip and stone isessential for effectiveness of ultrasonic lithotripsy.

Lasers are known as an alternative source of energy in lithotripsy,especially for the destruction of renal and biliary stones. Varioustypes of laser lithotripsy probes with a variety of laser sources,including pulsed dye laser, alexandrite laser, neodymium laser, holmiumlaser and other lasers, have been developed.

Electrohydraulic lithotripsy (EHL) has been an accepted form of therapyfor the destruction of urinary stones both in the human bladder andwithin the individual ureters. EHL is extremely effective in breakinglarge urinary stones into pieces small enough for basket extraction orsimple passage. When EHL is selected to affect the destruction of thestone, the EHL probe is placed in proximity to the stone. By means of anelectrical discharge, a shock wave is produced which impacts the surfaceof the stone and produces tiny cracks. When enough cracks have beenmade, the stone shatters into small pieces. The individual pieces canthen be attacked one at a time, or they can further be removed by basketextraction.

A lithotripsy technique of electro-impulse destruction of materials isalso known in the art (see, for example, U.S. Pat. No. 7,087,061 toChernenko, et al). Contrary to electrohydraulic destruction, employingelectrodes which are not in direct contact with the object,electro-impulse destruction utilizes a probe with electrodes which areplaced directly on the object's surface. This technique is based on theVorob'evs effect that provides certain features of the dischargeobserved when a solid dielectric in contact with two rodlike electrodesis placed in a liquid dielectric medium, and a voltage pulse withincreasing front is applied to the electrodes. According to this effect,when the pulse front slope is small (e.g., the pulse rise time is morethan about 0.5 microseconds), the discharge develops in the surroundingliquid over the solid dielectric surface rather than penetrating intothe solid body. On the other hand, in the case of a sufficiently largeslope of the pulse front, the discharge propagates through the solid andproduces its fracture with cleavage of the surface fragments (see, forexample, G. A. Masyats, Technical Physics Letters, Vol. 31, No. 12,2005, pp. 1061-1064. Translated from Russian from Pis'ma v ZhurnalTekhnicheskoi Fiziki, Vol. 31, No. 24, 2005, pp. 51-59).

A problem associated with lithotripsy probes is that the calculi are notcaptured during treatment. For example, a stone can be pushed along theureter towards the kidney in response to efforts to treat it. Likewise,the stone can also move to the side of the catheter and wedge betweenthe ureter wall and the catheter.

There are known medical devices combining a lithotripsy probe used tobreak calculi with a retrieval collapsible wire basket that allows asecure hold on a urinary or biliary stone, while the destructive forcesof the lithotripsy probe are used to shatter the stone. One of theadvantages of such combined lithotripsy devices is in the fact that theoperator using such a device is not required to change a lithotripsyprobe and a retrieval basket in the middle of the procedure, within thevery restrictive confines of the urinary or biliary tract.

For example, U.S. Pat. No. 5,176,688 to Narayan, et al. describes astone extractor and method in which a stone is captured in a retrievalbasket at the distal end of an elongated tubular member and broken intopieces while it is held by the basket. The stone is broken up by areciprocating shaft which extends through the tubular member into thebasket and is driven toward the stone by a spring to provide aneffective hammering action without injuring the surrounding tissue. Thestone is removed from the body by withdrawing the tubular member fromthe body with the pieces of the stone in the basket.

U.S. Pat. No. 5,397,320 to Mitchell, et al. describes a laparoscopicsurgical device which comprises an elongated shaft having a plurality ofelectrically conductive flexible ribs connected to the distal end of theshaft and to one another to form a cage or basket. Upon placement of anorganic body in the cage, the ribs are electrically energized. Theorganic body is pressed against the ribs to dissect the ribs in a singlecauterization operation.

U.S. Pat. No. 6,319,261 to Bowers describes a combination lithotripsydevice for the destruction of calculi such as urinary stones in thehuman bladder, individual urinary ureters, the biliary tract, or otherlocations in the human body. More specifically, the device includes anelectrohydraulic probe combined with a basket which consists of multipleelectrical conduit wires that act both as electrical conduits andcollectively act as a grasping device.

SUMMARY OF THE INVENTION

There is a need in the art for, and it would be useful to have a novelmedical device combining lithotriptic and retrieval features, which iscapable to be safely introduced into the confined space of theindividual ureter, urinary bladder or biliary tract, to secure theconcretion, shatter the concretion into smaller pieces, and retrieve thepieces from the body tracts.

It would also be advantageous to have a method for destruction andremoval of the concretion utilizing the device of the present invention.

The present invention satisfies the aforementioned need by providing anovel medical device for entrapping concretions in ducts and cavities ofa living body, breaking them into smaller pieces and removing the piecesfrom the body. The medical device includes a dilator sheath, alithotripsy probe, a tubular member mounted within the dilator sheathand accommodating the lithotripsy probe, and a retrieval basket coupledto the tubular member.

The dilator sheath is adapted to penetrate into a passage of the body toreach the location where the concretion to be shattered into smallerpieces is located. The lithotripsy probe is configured for shatteringthe concretion into smaller pieces. The tubular member has a proximalmember end, a distal member end and an axially extending inner lumenprovided within the tubular member to permit the lithotripsy probe to beinserted into the tubular member from the proximal end. The retrievalbasket is configured for entrapping and retaining the concretion and thesmaller pieces for their extraction from the body. It should be notedthat in the description and claims that follow, the terms “proximal” and“distal” are used with reference to the operator of the medical device.

The retrieval basket comprises a structure that has a basket proximalportion and a basket distal portion. The structure is constituted by aplurality of filaments extending from a basket proximal end towards abasket distal end, and then returning to the proximal end after forminga plurality of filament loops in the basket distal portion, and aplurality of filament strands at the basket proximal portion. The sidesof the filament loops are connected to the sides of adjacent loops atthe distal portion of the basket to form a net defining a distal openingat the basket distal end and a plurality of side openings along thestructure of the basket. The distal opening in the basket has suchdimension so that to permit the lithotripsy probe to protrude throughthe distal opening.

According to an embodiment of the present invention, the connection ofthe loops is achieved by twisting the filaments forming thecorresponding sides of the adjacent loops by at least one turn.

The filaments forming the structure of the basket can be eithersingle-core wires or multiwire strands.

According to one embodiment of the present invention, the filamentsforming the structure of the basket are made of a metallic materialhaving super elastic and thermo-mechanical shape memory characteristics.For example, the metallic material can be a NiTi based alloy. Likewise,the metallic material can be stainless steel.

When desired, the metallic material can include a radiopaque material.The radiopaque material can, for example, be at least one of thefollowing metals: Pt, Au, Ag, Pd, W, Nb, Co, and Cu.

According to another embodiment of the present invention, the filamentscan be made of a core tube containing an axially disposed radiopaquewire.

According to a further embodiment of the present invention, the medicaldevice can comprise one or more radiopaque markers attached to one ormore loops.

When the filaments forming the structure of the basket are multiwirestrands, they can include a central core wire and at least one anotherwire twisted about the central core wire. When desired, such anotherwire is made of a material having a level of radiopacity greater thanthe level of radiopacity of the central core wire.

According to yet a further embodiment of the present invention, thefilaments are made of non-metallic material. Examples of thenon-metallic material include, but are not limited to, Capron and Nylon.

According to an embodiment of the present invention, the dilator sheathis made of a flexible strong material that can, for example, be aplastic material or a composite material. The tubular member is adeflectable tube. Examples of materials suitable for the tubular memberinclude, but are not limited to, polyimide, nylon, and polyester.

According to an embodiment of the present invention, the tubular memberdistal end has a hollowed-out portion for connecting the tubular memberto the filament strands of the retrieval basket along the surfacecircumference of the hollowed-out portion.

According to an embodiment of the present invention, the medical devicecomprises a tube put on the filament strands at the hollowed-outportion. Preferably, but not mandatory, the tube is made of athermo-shrinkable material.

Examples of the lithotripsy probe include, but are not limited to, anelectro-hydraulic lithotripsy probe, an electro-impulse lithotripsyprobe, an ultrasonic wave lithotripsy probe, a mechanic lithotripsyprobe, and a laser light lithotripsy probe.

The aforementioned need is also satisfied by providing a method forbreaking a concretion in a body it into smaller pieces and removing thepieces from the body by using a medical device of the present invention.

A particular order of the method steps depends on the size of aconcretion. When the concretion is smaller than the side openings in thestructure of the basket, the concretion can first be captured by thebasket and immobilized therein. The entrapped concretion can beshattered into pieces. In this case, the method includes the steps of:

(a) inserting the medical device in a basket closed position through anendoscope into the body into proximity with the concretion;

(b) manipulating the tubular member and the dilator sheath for openingthe retrieval basket, entrapping the concretion in the retrieval basket,and closing the basket around the concretion;

(c) manipulating the lithotripsy probe for protruding thereof from thelumen in the tubular member and bringing thereof into proximity with theconcretion entrapped in the retrieval basket;

(d) energizing the lithotripsy probe to cause the concretion to breakinto smaller pieces; and

(e) removing the medical device from the body together with at least onepiece of the concretion immobilized within the basket.

On the other hand, when the concretion is relatively large, and cannotpass through the side openings in the structure of the basket, theconcretion should first be shattered into pieces by using thelithotripsy probe. In this case, the method includes the steps of:

(a) inserting the medical device in a basket closed position through anendoscope into the body into proximity with the concretion;

(b) manipulating the lithotripsy probe for protruding thereof from thelumen in the tubular member and the distal opening of the basket tobring the lithotripsy probe into proximity with the concretion entrappedin the retrieval basket;

(c) energizing the lithotripsy probe to cause the concretion to breakinto smaller pieces;

(d) manipulating the tubular member and the dilator sheath for openingthe retrieval basket, entrapping at least one piece of the concretion inthe retrieval basket, and closing the basket around the piece; and

(e) removing the medical device from the body together with the piece ofthe concretion immobilized within the basket.

There has thus been outlined, rather broadly, the more importantfeatures of the invention in order that the detailed description thereofthat follows hereinafter may be better understood. Additional detailsand advantages of the invention will be set forth in the detaileddescription, and in part will be appreciated from the description, ormay be learned by practice of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to understand the invention and to see how it may be carriedout in practice, preferred embodiments will now be described, by way ofnon-limiting example only, with reference to the accompanying drawings,in which:

FIG. 1 is a schematic side cross-sectional view of a distal portion of amedical device in a deployed position, according to one embodiment ofthe present invention;

FIGS. 2A and 2B illustrate a schematic side elevational view, partiallybroken away, of a distal portion of the medical device shown in FIG. 1,showing a foreign object arranged in front of the retrieval basket beingin an opened position and in a retracted position, correspondingly;

FIG. 2C illustrates a schematic side elevational view, partially brokenaway, of a distal portion of the medical device shown in FIG. 1, showinga foreign object being entrapped inside the basket;

FIG. 3 illustrates a plan view of a distal portion of a medical deviceof the present invention having a retrieval basket according to oneembodiment of the present invention;

FIG. 4 illustrates a plan view of a distal portion of a medical deviceof the present invention having a retrieval basket according to anotherembodiment of the present invention;

FIG. 5 illustrates a plan view of a distal portion of a medical deviceof the present invention having a retrieval basket according to afurther embodiment of the present invention;

FIG. 6A illustrates schematically the juxtaposition of the concretionand the impact tip of the electro-hydraulic lithotripsy probe;

FIG. 6B illustrates schematically the juxtaposition of the concretionand the impact tip of the electro-impulse lithotripsy;

FIG. 7 illustrates schematically the juxtaposition of the concretion andthe impact tip of the ultrasonic lithotripsy probe;

FIG. 8 illustrates schematically the juxtaposition of the concretion andthe impact tip of the mechanical lithotripsy probe; and

FIG. 9 illustrates schematically the juxtaposition of the concretion andthe impact tip of the laser lithotripsy probe.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The principles of the method for the medical device according to thepresent invention may be better understood with reference to thedrawings and the accompanying description, wherein like referencenumerals have been used throughout to designate identical elements. Itbeing understood that these drawings which are not necessarily to scale,are given for illustrative purposes only and are not intended to limitthe scope of the invention. Examples of constructions, materials,dimensions, and manufacturing processes are provided for selectedelements. Those versed in the art should appreciate that many of theexamples provided have suitable alternatives which may be utilized.

FIG. 1 illustrates a schematic side cross-sectional view of a distalportion of a medical device 10 in a deployed position, according to oneembodiment of the present invention. The medical device 10 includes anelongated, catheter-like tubular member 11 which has a tubular memberproximal end (not shown), a tubular member distal end 12 and an axiallyextending inner lumen 13 provided within the tubular member 11 to permita lithotripsy probe 14 to be inserted into the tubular member 11 fromthe proximal end. The tubular member 11 is a deflectable tube fabricatedof a relatively stiff yet somewhat pliant material, which permits thedevice to be introduced into a patient's body (not shown) along atortuous path. Examples of materials suitable for the tubular member 11include, but are not limited to, polyimide, nylon, polyester, etc.

The lithotripsy probe 14 is mounted within the inner lumen 13 so that itmay be extended or retracted by an operator (not shown). It should benoted that the present invention is not limited to a specific kind oflithotripsy technique for breaking concretions. Generally, thelithotripsy probe 14 includes an impact tip 141, a control cable (rod)142 coupled to the tip 141, and an energy unit (not shown) coupled tothe control cable 142. In operation, the impact tip 141 is placedagainst the concretions, e.g., stone, (not shown) and the energy unit isactivated to provide energy sufficient for breaking the stone into muchsmaller fragments. Various types of the lithotripsy probe 14 suitablefor the purpose of the present invention will be described more fullybelow in connection with FIGS. 6A, 6B, 7, 8 and 9.

The medical device 10 further includes a dilator sheath 15 formed as atubular catheter. The dilator sheath 15 is a thin-walled, cylindricalflexible tube adapted to penetrate into a body passage (not shown) toreach the location where the concretion to be shattered into smallerpieces, is located. The catheter-like tubular member 11 is mountedwithin the dilator sheath 15, and can be manipulated by the operatorfrom the outside at the sheath's proximal end (not shown). For example,the dilator sheath 15 can be made of a flexible, durable, strong plasticmaterial, such as polyimide, polyvinyl chloride, nylon, teflon, etc. Thedilator sheath 15 can also be made of a composite material, such as awire mesh or a coil, (e.g., stainless steel coil). When desired, thesheath 15 may be multi-layered with different materials in order toprovide a graduated bending and stiffness characteristic over itslength.

The medical device 10 further includes a retrieval basket 16 coupled tothe catheter-like tubular member 11 at the tubular member distal end 12.The retrieval basket 16 is used in a ureter, urinary bladder or biliarytract (not shown) to trap the concretion that can be shattered intosmaller pieces by the lithotripsy probe 14, and to retrieve the piecesfrom the body tracts.

A plan view of the retrieval basket 16 in a deployed (opened) positionis illustrated in FIG. 1, according to one embodiment of the presentinvention. In general, the structure of the retrieval basket 16comprises a proximal portion 161 and a distal portion 162, and isconstituted by a plurality of filaments fabricated from one or morewires that extend from a basket proximal end 163 towards a basket distalend 164 and then return after winding to the proximal end 163 to form aplurality of filament loops 165. After forming the loops in the distalportion 162, the filaments are bound together in filament strands 166 atthe proximal portion 161 of the basket.

According to one embodiment of the invention, each filament forming thestructure of the basket is a single-core wire. According to anotherembodiment of the invention, each filament is a multi-wire strand.

The filaments of the retrieval basket 16 can each have a cross-sectionaldiameter in the range of from about 0.05 mm to about 0.15 mm. Thediameters of the filaments may vary from wire-to-wire and/or along thelengths of each wire.

The filaments utilized for the fabrication of the retrieval basket 16are made of a suitable material that is suitably biocompatible and hasthermo-mechanical shape memory and/or superelastic properties. Accordingto one embodiment of the invention, the filaments are made of a metallicmaterial. For example, the metallic material can be selected from a NiTibased alloy (e.g., Nitinol), stainless steel and other materialspossessing good shape memory, elastic or superelastic characteristics.According to another embodiment of the invention, the filaments are madeof non-metallic material, e.g. Capron, Nylon, etc.

According to a still further embodiment of the invention, the filamentsof the basket are covered by an insulating layer. The insulating layercan, for example, be made of Teflon. The advantage of Teflon is itsthermal resistance and low coefficient of mechanical friction, whichleads to an additional reduction of traumatism.

Preferably, but not mandatory, the filaments are radiopaque, so as topermit them to be visualized by a fluoroscope with respect to the objectto be retracted. Thus, according to one example, in order to provideradiopacity, the metallic material from which the filaments are made caninclude a material which provides radiopacity, e.g., a noble metal, suchas gold, tantalum, platinum, etc. Likewise, the metallic material can bealloyed with one or more metals selected from Pd, W, Nb, Co, Cu, etc.

According to another example, the filaments are made of a core tube(cannular strand) containing an axially disposed radiopaque wire.

According to yet another example, the filaments can have radiopaqueparts of a predetermined length. These radiopaque parts can form thedistal portion 162 of the basket or at least a part of the distalportion.

Radiopacity can also be improved through coating processes such assputtering or plating a radiopaque material onto the filaments, or thebasket fabricated from these filaments, thereby to provide a radiopaquecoating layer on the filaments.

Likewise, radiopacity can yet be improved by using radiopaque markers(not shown) which can be attached to or placed around the filamentsforming the basket. In this manner, materials which have higherradiopacity than the basket structure itself, such as gold, tantalum orplatinum, can be utilized as markers and be strategically placed alongthe body of the basket to increase the visualization of the basket. Forexample, the retrieval basket can comprise one or more radiopaquemarkers (not shown) attached to or placed around the filaments formingone or more filament loops 165 in the distal portion 162. For example,the radiopaque marker can be a ferrule put on the filament.

According to another embodiment of the invention, the filaments can bemulti-wire strands. In such a case, in order to improve radiopacity, themulti-wire strands can include a central core wire and at least oneanother wire twisted about said central core wire which is made of amaterial having a level of radiopacity greater than the level ofradiopacity of said central core wire. Examples of such a materialinclude, but are not limited to, Pt, Au, Pd, Ta, etc.

According to one embodiment of the invention, each filament originatesfrom a certain point at the basket proximal end 163, and extends towardsthe basket distal end 164 to form a loop. After forming the loop, thefilament returns to the original point at the basket proximal end 163 toform one of the basket filament strands 166 in the proximal portion 161.

According to another embodiment of the invention, each filament extendsfrom a certain point at the basket proximal end 163, and then, afterenwinding with other filaments, arrives at another point at the basketproximal end 163, where the filaments meet with one or more otherfilaments. In this case, each filament strand 166 is formed by two ormore different filaments that correspond to the sides of adjacent loops.

Description of various embodiments of the retrieval basket 16 of themedical device 10 will be described more fully below in connection withFIGS. 3-5.

At the basket proximal end 163, the filament strands 166 are connectedto the catheter-like tubular member 11 along the surface circumferenceof the tubular member distal end 12. A joining portion 167 may, forexample, be a hollowed-out portion at the distal end of the tubularmember 11 (as shown in FIG. 1). The axial dimension of hollowed-outportion can, for example, be in the range of about 15 mm-25 mm.Alternatively, joining portion 167 can include a separate ferrule, suchas a hollow cannula made of metal, e.g., stainless steel, etc.

The filaments from the basket strands 166 can be trimmed and coupled tothe tubular member 11 along the surface circumference of the tubularmember distal end 12 by one or more connecting means.

In one embodiment, the filament strands 166 of the retrieval basket canbe directly connected to the tubular member 11. For instance, thefilament strands 166 may be soldered, brazed or welded to the tubularmember 11 at the joining portion 167. Likewise, a medically-acceptableadhesive may also be used to secure or join the filament strands 166 tothe tubular member 11. An example of the adhesive includes, but is notlimited to, LOCTITE® 4011 cyanoacrylate.

In order to increase mechanical strength, a thin tube 168 can be put onthe filament strands 166 at the joining portion 167, as shown in FIG. 1.The tube 168 can be made of a thermo-shrinkable material. An example ofthe material suitable for the tube 168 includes but is not limited toPolytetrafluoroethylene (PTFE). The wall thickness of the tube 168 can,for example, be in the range of about 0.005 mm-0.01 mm.

In another embodiment, a separate ferrule (not shown), may be used toconnect the filament strands 166 or loops to the tubular member 11. Theferrule can be joined to the tubular member 11 and to the filamentstrands, preferably, by soldering, welding or brazing, although otherknown techniques, such as gluing, may also be used. For instance, ifsoldering is used, the end of the tubular member 11 is first etched,preferably with acid, followed by neutralizing and drying. Flux is thenapplied to both the tubular member 11 and the cannula, the two aresoldered together, and excess solder is removed. Afterwards, the partsshould be neutralized, dried and cleaned.

At the distal portion 162 of the basket, the filament loops 165 areoverlapped and/or interlaced with each other so as to form open spacesbetween the filaments. The filament loops 165 define a net that has adistal opening 169 at the basket distal end 164, and a plurality of sideopenings 170 along the basket's structure. Note that the term“overlapped” herein is assigned to such arrangement of the filamentsforming the filament loops, in which one element crosses otherfilaments, i.e., one of the filaments always being over or under theother filaments. The term “interlaced” herein is assigned to thesituation when at least one filament interweaves with the otherfilaments, i.e., one of the filaments passes first above the crossedfilament and then passes under the next crossed filament.

The distal opening 169 in the basket has such dimension so as to permitthe lithotripsy probe 14 to be protruded through the distal opening 169in order to bring the probe 14 into proximity with the object (notshown), when it is located in front of the basket. This provisionpermits to apply destruction energy to relatively large concretions. Alarge concretion can only be located in front of the basket, because theconcretion cannot pass through the side openings 170 to be captured andentrapped within the basket, owing to the big size of the concretion.After the breaking of such a concretion into parts, the smaller piecescan be captured and retained in the basket for their further destructioninside the basket, or removal from the patient's body.

The method for removing concretions within ducts and cavities of aliving body according to the present invention involves the followingsteps. According to one embodiment of the present invention, anendoscope (not shown) steerable by an operator is first inserted intothe patients body tract and/or cavity into proximity with the concretionby known means, for example, through a surgical incision, through theurethra or through any other duct. The endoscope can, for example, be acystoscope, a urethroscope or another suitable device that includes botha light source and fiber optics so that the stone can be seen when thedevice is properly inserted. Thereafter, the medical device of thepresent invention is inserted through the endoscope into the body.

When a concretion is relatively large, and the basket cannot pass beyondthe concretion for its capturing or it cannot pass through the sideopenings in the structure of the basket, the concretion should first beshattered into pieces by using the lithotripsy probe 14.

FIGS. 2A and 2B illustrate two examples of operation of the medicaldevice shown in FIG. 1 when an object (concretion) 21 is arranged infront of the retrieval basket 16. It should be understood that when theobject is arranged in front of the retrieval basket 16, in operation,the basket can be either open or closed. Specifically, when the basketis fully open, as shown in FIG. 2A, the opened basket 16 forms a cage toallow the pieces of the shattered object to enter into the side openings170 left between the filaments. In order to shatter the object, thelithotripsy probe 14 can be protruded through the distal opening 169 forbringing the impact tip 141 into proximity with the object 21. Dependingon the lithotripsy technique, the end of the impact tip 141 of thelithotripsy probe 14 can be close to, or in direct contact with asurface of the object 21.

Likewise, the basket 16 may only be partially opened or even becompletely retracted inside the sheath 15. As shown in FIG. 2B, thelithotripsy probe 14 can be protruded through the distal opening 169 andbrought into contact with the object, whereas the basket is locatedwithin the sheath 15.

After bringing the lithotripsy probe 14 into proximity with the object21, the probe is energized for applying destruction energy to theobject. After the shattering of the object into pieces, the basket canbe advanced for opening and entrapping the pieces having smallerdimensions than the dimensions of the original object 21.

The retrieval basket 16 and the sheath 15 can move relative to eachother to open and close the basket 16. Depending on the manipulation ofthe tubular member 11, the basket 16 may either retract inside thesheath 15, to allow penetration of the sheath 15 via a passage, orprotract from the sheath 15. In the protracted position, the basket 16is open, due to the elasticity of the filament material, and forms acage to thus allow entry of an object (e.g., concretion) inside thebasket through the open spaces left between its adjacent filaments.Further retraction of the basket 16 inside the sheath 15 results in thecage collapsing and entrapping the object in the basket.

When the object is relatively small, distal end portion of the basket ismoved slightly beyond the stone to be removed. Then, the basket isopened, and the instrument is manipulated to capture the concretion inthe basket. Once the concretion has been captured, the basket is closedaround the concretion to retain the concretion in the basket.

FIG. 2C illustrates an example of operation of the medical device shownin FIG. 1 when an object (concretion) 21 is entrapped inside theretrieval basket 16. Depending on the lithotripsy technique, the end ofthe impact tip 141 of the lithotripsy probe can be brought to be closeto, or in direct contact with a surface of the object 21. Then, thelithotripsy probe 14 is energized for breaking the concretion into muchsmaller fragments. Large fragments of the concretion are retained in thebasket, while, at least in the case of kidney stones, smaller fragmentsmay escape from the basket, and subsequently pass out of the body withthe urine. Finally, removal of the sheath 15 together with the endoscopewill enable the whole device to be removed from the body organ togetherwith the object immobilized within the basket.

The entire medical device of the present invention may be constructed ina number of sizes and lengths, so as to be able to pass through thevarious sizes of ducts and cavities of a living body and the variousdimensions of working channels of commercial cystoscopes, ureteroscopesor other endoscopes.

Generally speaking, the overall axial length of the device of thepresent invention can, for example, be in the range of from about 1 m toabout 3 m. Shorter or longer overall lengths are also contemplated asmay be required to effect a particular procedure.

It should be understood that the overall diameter of the cross-sectionof the medical device of the present invention should in use be smallenough to accommodate any working channel through which the device ofthe invention is used. Specifically, the overall diameter of thecross-section of the lithotripsy probe 14 depicted in FIGS. 1, 2A and 2Bcan, for example, be from about 0.2 mm to about 2 mm. It will beunderstood that the inner diameter of the tubular member 11 should begreat enough to provide axial movement of the lithotripsy probe 14within the lumen 13. The outer diameter of the tubular member 11 can,for example, be in the range of from about 0.3 to about 2.5 mm, whereasthe outer diameter of the tubular member 11 at the joining portion 166,where the filament strands are attached to the tubular member 11, can bein the range of from about 0.4 mm to about 2.8 mm.

The inner diameter of the dilator sheath 15 can, for example, be in therange of from about 0.4 to about 3 mm, whereas the outer diameter of thedilator sheath 15, can be in the range of from about 0.44 to about 3.5mm.

For example, when the outer cross-sectional diameter of the dilatorsheath 15 is 1.00 mm (3Fr) or smaller the entire medical device of thepresent invention may be used together with the commercial ureteroscopeDUR-8 (available from ACMI) that has dimensions of the working channelsof 1.2 mm (3.6 Fr).

Referring now to FIGS. 3-5, various configurations of the retrievalbasket 16 will be described hereinbelow.

FIG. 3 shows a plan view of a distal portion of a medical device of thepresent invention having a retrieval basket 30 for entrapping andretaining a foreign object (not shown) in a deployed position, accordingto one embodiment of the present invention. The structure of theretrieval basket 30 comprises a proximal portion 31 and a distal portion32. The structure is constituted by a plurality of filaments thatoriginate from a basket proximal end 33 of the proximal portion 31, thenextend towards the distal portion 32, and finally return to the end 33,thereby forming a plurality of filament loops 34 in the distal portion32, and a plurality of filament strands 35 in the proximal portion 31.In accordance with the embodiment shown in FIG. 3, each filament strand35 is formed by twisting the same filament that extends from the end 33towards the distal portion and then returns to the end after forming thecorresponding wire loop 34.

In the distal portion 32, each side of each wire loop 34 is directlyconnected to a side of an adjacent loop. According to one embodiment ofthe invention, connection 36 of the sides of the loops 34 in the distalportion 32 is achieved by twisting each pair of the filaments formingthe corresponding sides of the neighboring loops 34 by one or moreturns. Likewise, the connection 36 of the sides of the neighboring loopscan also be achieved by soldering, brazing, gluing, etc. Connecting thesides of the loops provides structural rigidity and dilatation abilityto the basket.

The filament loops 34 define a net that has a distal opening 37 at abasket distal end 38, where the loops 34 are not bound, and a pluralityof side openings 39 along the basket's structure. The distal opening 37in the basket has such dimension so that to permit the lithotripsy probe14 to be protruded through the distal opening 37, when desired. In turn,the side openings 39 are configured for enabling the relatively smallconcretions to pass through to be captured and entrapped within thebasket.

Referring to FIG. 4, there is shown a plan view of a distal portion of amedical device of the present invention having a retrieval basket 40 forentrapping and retaining a foreign object (not shown) in a deployedposition, according to another embodiment of the present invention. Thestructure of the retrieval basket 40 comprises a proximal portion 41 anda distal portion 42. The structure is constituted by a plurality offilaments that originate from a basket proximal end 431 and are boundtogether at the proximal portion 41 to form a plurality strands 44 (fourstrands are shown in FIG. 4). In the distal portion 42 the strands 44ramify at branching points 45 into sub-strands 46, which in turn ramifyat branching points 47. After ramification of the strands 44 and thesub-strands 46, the filaments form a plurality of filament loops 48(four filament loops are shown in FIG. 4). Sides of each loop 48 areconnected to the sides of two adjacent neighboring loops. The places ofconnections are indicated by a reference numeral 49. The connection ofthe sides of the loops 48 can, for example, be achieved by twisting thefilaments forming the corresponding sides of the neighboring loops byone or more turns. Likewise, the connection of the sides of theneighboring loops can also be achieved by soldering, brazing, gluing,etc.

The filament loops 48 define a net that has a distal opening 481 at abasket distal end 432, where the loops 34 are not bound, and a pluralityof side openings 482 along the basket's structure. The distal opening481 in the basket has such dimension so as to permit the lithotripsyprobe (not shown in FIG. 4) to be protruded through the distal opening481, when desired. In turn, the side openings 482 are configured forenabling the relatively small concretions to pass through to be capturedand entrapped within the basket.

Referring to FIG. 5, there is shown a plan view of a distal portion of amedical device of the present invention having a retrieval basket 50 forentrapping and retaining a foreign object (not shown) in a deployedposition, according to a yet another embodiment of the presentinvention. According to this embodiment, the structure of the retrievalbasket 50 has a petal shape and comprises a proximal portion 51 and adistal portion 52. The structure is formed by a plurality of filamentsthat extend from an end 53 of the proximal portion 51 towards the distalportion 52 and then return to the end 53 to form a plurality of filamentloops 54. In the proximal portion 51, each side 55 of each loop 54 isdirectly connected to a side 55 of an adjacent loop 54 at one or morepoints between the end 53 and a distal connection point 56.Specifically, each side 55 of each loop 54 is connected to a side of anadjacent loop at continues length sections, thereby forming a pluralityof strands 57 at the basket proximal portion. This feature providesstructural rigidity and dilatation ability to the basket. However, theloops 54 are not interconnected in the distal portion 52. Specifically,the loops 54 deploy radially outward and away from each other in thedistal portion 52 when the basket is deployed outside the dilator sheath15.

According to one embodiment of the invention, the filament loops 54 aregenerally flat and planar. According to another embodiment of theinvention, each side 55 of the filament loops is slightly bent orarcuate into an arc (C-shaped configuration). Such a configuration canenhance the ability to slip the loops over the foreign object and graspit. According to still another embodiment of the invention, each side 55of the filament loops 54 is slightly undulated into a somewhat S-shapedconfiguration. Such a configuration can facilitate retraction of thebasket into the sheath 15.

According to one embodiment of the present invention, the connection ofthe sides 55 of the loops 54 in the proximal portion 51 is achieved bytwisting each pair of the corresponding sides 55 by one or more turnsand forming twisted parts of the strands 57. Likewise, the connection ofthe sides of the neighboring loops can also be achieved by soldering,brazing, gluing, etc.

From the foregoing description it should be appreciated that retrievalbaskets of the medical device constructed in accordance with the presentinvention, can comprise a variety of user desired shapes, number ofloops, shape of the loops, types of connection of the loops in theproximal portion and types of connection of the loops to a manipulationrod. Thus, although the exemplary baskets 30, 40 and 50 having fourfilament loops 34, 48 and 54 are illustrated in FIGS. 3-5, respectively,showing the baskets in accordance with different embodiments, theinvention is not limited by such basket structures. Generally, anydesired number of the loops equal to or greater than two may befabricated, mutatis mutandis.

Turning now to FIGS. 6A, 6B, 7, 8 and 9, various types of thelithotripsy probe 14 suitable for the purpose of the present inventionwill be described hereinbelow.

According to one embodiment of the invention, the lithotripsy probe 14provides energy of a shock-wave of electro-hydraulic lithotripsy (EHL).FIG. 6A shows schematically the impact tip 141 of the lithotripsy probe14 used in EHL, and location of a concretion 61 juxtaposed against theimpact tip 141. The impact tip 141 includes a high voltage centralelectrode 62, which is surrounded by an annular electrode 63, formed asa tubular member concentric with the central electrode 62. The object61, e.g., a calculus, is distant from both electrodes 62 and 63, and dueto a gap 64 none of the electrodes is in direct electrical contact withthe object 61. The energy unit 143 includes an EHL pulse generator (notshown) coupled to the central electrode 62 and the annular electrode 63via the control cable 142.

In operation, a series of high voltage pulses of sufficiently shortduration, to avoid harm to human tissues, is generated in an electricalpulse generator (not shown). Pulses therefrom are directed to the impacttip 141 to produce a spark discharge between the electrodes 62 and 63.Shock waves 65 produced by the spark discharge propagate towards theconcretion 61 through the gap 64 and break it into peaces. It should benoted that no discharge channel is formed within the calculus itself.

Various EHL pulse generators are commercially available. Examples ofcommercially available EHL generators include, but are not limited to,Karl Storz 27080 system, Model 2137 from Richard Wolf, GmbH, etc.

According to another embodiment of the invention, the lithotripsy probe14 is based on electro-impulse destruction. The lithotripsy probe 14used in electro-impulse destruction can be similar to the lithotripsyprobe used in EHL, which is shown in FIG. 6A. The difference betweenelectro-impulse destruction and the EHL destruction is in the mutualarrangement of the probe and object and in the slope of the voltagepulse utilized for spark discharge. FIG. 6B shows schematically thelocation of the object 61, with respect to the impact tip 141 atelectro-impulse destruction. In this case, at least one of theelectrodes 62 and 63 (or both electrodes 62 and 63) is (are) placeddirectly on the object surface to locate the spark discharge within thebulk of the object 61. Due to this provision the high voltage sparkdischarge produces spark channel within the object itself. Due torelease of impulse energy within the spark channel the pressure withinthe channel dramatically increases, diameter of the channel enlargescausing tensile stresses within the object. The object can beefficiently fragmented and destroyed due to these tensile stresses incombination with hydraulic pressure of the surrounding liquid medium andcollisions with the fragments of the object.

It should be understood that the lithotripsy probe 14 is not bound byany specific configuration of the electrodes 62 and 63. For example, theannular electrode 63 can be combined with miniaturized grasping forcepsconfigured for grasping the foreign body anywhere along its length asdescribed in U.S. Pat. No. 7,087,061 to Chernenko, et al., thedisclosure of which is incorporated hereby by reference into thisdescription.

In practice, for calculi appearing in a living body that have dimensionsin the range of from about 3 mm to several centimeters, the electricalpulses supplied to electrodes can be defined by the followingparameters: rise time of the pulse front is less than about 100nanoseconds, preferably less than about 40 nanoseconds; duration of thepulse is less than about 5 microseconds, preferably 0.5-0.3microseconds, pulse energy is in the range of about 0.1-1 Joule, impulseamplitude is in the range of about 5-30 kV. The preferred configurationof the pulses is rectangular.

Referring to FIG. 7, according to a further embodiment of the invention,the lithotripsy probe 14 provides energy of ultrasonic wave for breakingconcretions. In this case, the lithotripsy probe 14 includes anultrasonic-vibration generation source 71 mounted either in the energyunit 143 or in the impact tip 141, and adapted for irrigation fluid nearthe impact tip 141. When the ultrasonic-vibration generation source ismounted in the energy unit 143, the control cable 142 can include anultrasonic transmission line for transferring the ultrasonic energy tothe tip 141. In operation, the tip 141 is juxtaposed against theconcretion 73. At the tip, an ultrasonic wave formed by the probe 14 isdirected towards the concretion 73.

It should be noted that the present invention is not limited to anyspecific implementation of the ultrasonic probe. Examples of ultrasonicprobes suitable for the purpose of the present invention are describedin U.S. Pat. No. 4,046,150 to Schwartz, et al.; U.S. Pat. No. 5,403,324to Ciervo, et al.; and U.S. Pat. No. 6,613,056 to Brumbach, et al., thedisclosure of which is incorporated hereby by reference into thisdescription.

Referring to FIG. 8, according to yet another embodiment of theinvention, the lithotripsy probe 14 provides mechanical energy forbreaking concretions. In this case, the control cable 142 of thelithotripsy probe 14 includes or represents a relatively stiff rod withthe tip of the rod placed against the concretion 81. The rod is adaptedfor reciprocal movement between axially advanced and retracted positionsfor breaking the concretion into smaller pieces for easier removal fromthe body (not shown) in the retrieval basket. When desired, the energyunit 143 can include means (not shown) for moving the rod back and forthto impact the tip upon the concretion with a hammering action. Suchmeans are known per se (see, for example, U.S. Pat. No. 5,176,688 toNarayan, et al., the disclosure of which is incorporated hereby byreference into this description), and therefore will not be expoundedhereinbelow. When desired, the end of the tip 141 can include one ormore cutting teeth 82 for facilitation of the shattering function.

Referring to FIG. 9, according to yet another embodiment of theinvention, the lithotripsy probe 14 provides energy of laser light forbreaking a concretion 91. In this case, the lithotripsy probe 14includes a laser light source 92 mounted in the energy unit 143. Thelithotripsy probe 14 includes also a laser light guide mounted in orrepresented by the control cable 142. The laser light source 92 operatesat a predetermined frequency that is preferably selected to match a peakabsorption value of either the concretion or liquid in the vicinity ofthe concretion. The laser light emitted from the tip 141 and directedtowards the concretion 91 can be absorbed by either the concretion orthe liquid, thereby providing micro-explosions leading to concretiondestruction. Examples of laser light probes suitable for the purpose ofthe present invention are described in U.S. Pat. No. 4,887,600 toWatson, et al.; U.S. Pat. No. 5,059,200 to Tulip; U.S. Pat. No.5,041,121 to Wondrazek, et al., the disclosure of which is incorporatedhereby by reference into this description.

As such, those skilled in the art to which the present inventionpertains, can appreciate that while the present invention has beendescribed in terms of preferred embodiments, the concept upon which thisdisclosure is based may readily be utilized as a basis for the designingof other structures and processes for carrying out the several purposesof the present invention.

It should be understood that when desired the lithotripsy probe suitablefor the purpose of the present invention can be a combination of any twoor more lithotripsy techniques described above.

It should be understood that the medical device of the present inventionis not limited to a medical treatment of a human body. It can besuccessfully employed for medical treatments of animals as well.

Moreover, the present invention is not limited to fabrication of medicaldevices, thus the apparatus of the invention can be used to shatter andextract any type of article from a wide range of inaccessible locationssuch as inside a pipe or tube (for example, the waste outlet of adomestic sink) or inside a chamber within a large piece of machinerywhich would be difficult to dismantle.

Also, it is to be understood that the phraseology and terminologyemployed herein are for the purpose of description and should not beregarded as limiting.

In the method claims that follow, alphabetic characters used todesignate claim steps are provided for convenience only and do not implyany particular order of performing the steps.

It is important, therefore, that the scope of the invention is notconstrued as being limited by the illustrative embodiments set forthherein. Other variations are possible within the scope of the presentinvention as defined in the appended claims. Other combinations andsub-combinations of features, functions, elements and/or properties maybe claimed through amendment of the present claims or presentation ofnew claims in this or a related application. Such amended or new claims,whether they are directed to different combinations or directed to thesame combinations, whether different, broader, narrower or equal inscope to the original claims, are also regarded as included within thesubject matter of the present description.

What is claimed is:
 1. A medical device for breaking a concretion in abody into smaller pieces and removing the pieces from the body,comprising: a dilator sheath adapted to penetrate into a passage of thebody to reach the location where the concretion to be shattered intosmaller pieces is located; a lithotripsy probe configured for shatteringthe concretion into smaller pieces; a tubular member located within thedilator sheath and being not a part of the lithotripsy probe, thetubular member having a tubular member proximal end, a tubular memberdistal end and an axially extending inner lumen provided within thetubular member to permit the entire lithotripsy probe to be insertedinto the tubular member from the proximal end; and a retrieval basketcoupled to said tubular member at the tubular member distal end, andconfigured for entrapping and retaining the concretion and the smallerpieces for their extraction from the body, said retrieval basketcomprising a structure having a basket proximal portion and a basketdistal portion, and constituted by a plurality of filaments extendingfrom a basket proximal end towards a basket distal end, and thenreturning to the proximal end after forming a plurality of filamentloops in the basket distal portion, and a plurality of filament strandsat the basket proximal portion, each filament strand at the basketproximal portion being formed by twisting the same filament afterforming the corresponding filament loop.
 2. The medical device of claim1, wherein said retrieval basket is not a part of the lithotripsy probe.3. The medical device of claim 1, wherein said tubular member distal endhas a hollowed-out portion for connecting said tubular member to thefilament strands of the retrieval basket along the surface circumferenceof said hollowed-out portion.
 4. The medical device of claim 3,comprising a tube put on the filament strands at said hollowed-outportion.
 5. The medical device of claim 4, wherein said tube is made ofa thermo-shrinkable material.
 6. The medical device of claim 1, whereinsaid tubular member is a deflectable tube made from a material selectedfrom polyimide, nylon, and polyester.
 7. The medical device of claim 1,wherein said lithotripsy probe is selected from an electro-hydrauliclithotripsy probe, an electro-impulse lithotripsy probe, an ultrasonicwave lithotripsy probe, a mechanic lithotripsy probe, and a laser lightlithotripsy probe.
 8. The medical device of claim 1, wherein sides ofthe filament loops are overlapped or interlaced to provide a connectionwith each other so as to form a net defining a distal opening at thebasket distal end and a plurality of side openings along the structureof the basket; said distal opening in the basket has such dimension sothat to permit the lithotripsy probe to be protruded through said distalopening.
 9. The medical device of claim 8, wherein the connection of theloops is achieved by twisting the filaments forming the correspondingsides of the adjacent loops by at least one turn.
 10. The medical deviceof claim 1, wherein at the basket proximal end, the filament strands areconnected to said tubular member along the surface circumference of saidtubular member distal end.
 11. The medical device of claim 1, whereinthe filaments forming the structure of the basket are made of a metallicmaterial having super elastic and thermo-mechanical shape memorycharacteristics.
 12. The medical device of claim 11, wherein themetallic material is selected from NiTi based alloys and stainlesssteel.
 13. The medical device of claim 11 wherein the metallic materialincludes a radiopaque material.
 14. The medical device of claim 1wherein said filaments are made of a core tube containing an axiallydisposed radiopaque wire.
 15. The medical device of claim 1 comprisingat least one radiopaque marker attached to at least one loop in saiddistal portion.
 16. The medical device of claim 1, wherein the filamentsforming the structure of the basket are multiwire strands.
 17. Themedical device of claim 16 wherein said multiwire strands include acentral core wire and at least one another wire twisted about saidcentral core wire, said another wire being made of a material having alevel of radiopacity greater than the level of radiopacity of saidcentral core wire.
 18. The medical device of claim 1 wherein thefilaments are made of non-metallic material.
 19. A method for breaking aconcretion in a body it into smaller pieces and removing the pieces fromthe body by using a medical device comprising: a dilator sheath adaptedto penetrate into a passage of the body to reach the location where theconcretion to be shattered into smaller pieces is located; a lithotripsyprobe configured for shattering the concretion into smaller pieces; atubular member located within the dilator sheath and being not a part ofthe lithotripsy probe; the tubular member having a tubular memberproximal end, a tubular member distal end and an axially extending innerlumen provided within the tubular member to permit the entirelithotripsy probe to be inserted into the tubular member from theproximal end; and a retrieval basket coupled to said tubular member atthe tubular member distal end, and configured for entrapping andretaining the concretion and the smaller pieces for their extractionfrom the body, said retrieval basket comprising a structure having abasket proximal portion and a basket distal portion, and constituted bya plurality of filaments extending from a basket proximal end towards abasket distal end, and then returning to the proximal end after forminga plurality of filament loops in the basket distal portion, and aplurality of filament strands at the basket proximal portion, eachfilament strand at the basket proximal portion being formed by twistingthe same filament after forming the corresponding filament loop; themethod comprising: (a) inserting said medical device in a basket closedposition through an endoscope into said body into proximity with theconcretion; (b) manipulating the tubular member and the dilator sheathfor opening the retrieval basket, entrapping the concretion in theretrieval basket, and closing the basket around the concretion; (c)manipulating said lithotripsy probe for protruding thereof from thelumen in the tubular member and bringing thereof into proximity with theconcretion entrapped in the retrieval basket; (d) energizing saidlithotripsy probe to cause the concretion to break into smaller pieces;and (e) removing the medical device from the body together with at leastone smaller piece of the concretion immobilized within the basket.
 20. Amethod for breaking a concretion in a body it into smaller pieces andremoving the pieces from the body by using a medical device comprising:a dilator sheath adapted to penetrate into a passage of the body toreach the location where the concretion to be shattered into smallerpieces is located; a lithotripsy probe configured for shattering theconcretion into smaller pieces; a tubular member located within thedilator sheath and being not a part of the lithotripsy probe; thetubular member having a tubular member proximal end, a tubular memberdistal end and an axially extending inner lumen provided within thetubular member to permit the entire lithotripsy probe to be insertedinto the tubular member from the proximal end; and a retrieval basketcoupled to said tubular member at the tubular member distal end, andconfigured for entrapping and retaining the concretion and the smallerpieces for their extraction from the body, said retrieval basketcomprising a structure having a basket proximal portion and a basketdistal portion, and constituted by a plurality of filaments extendingfrom a basket proximal end towards a basket distal end, and thenreturning to the proximal end after forming a plurality of filamentloops in the basket distal portion, and a plurality of filament strandsat the basket proximal portion; wherein sides of the filament loops areconnected to the sides of adjacent loops at the distal portion of thebasket to form a net defining a distal opening at the basket distal endand a plurality of side openings along the structure of the basket; themethod comprising: (a) inserting said medical device in a basket closedposition through an endoscope into said body into proximity with theconcretion; (b) manipulating said lithotripsy probe for protrudingthereof from the lumen in the tubular member and the distal opening ofthe basket to bring said lithotripsy probe into proximity with theconcretion entrapped in the retrieval basket; (c) energizing saidlithotripsy probe to cause the concretion to break into smaller pieces;(d) manipulating the tubular member and the dilator sheath for openingthe retrieval basket, entrapping at least one piece of the concretion inthe retrieval basket, and closing the basket around the piece; and (e)removing the medical device from the body together with said at leastone smaller piece of the concretion immobilized within the basket.